摘要 |
<p>A vehicle oil-cooled brake comprising has an oil-containing chamber housing one or more rotatable brake discs (22,23) connected a with driveline shaft (150 and a brake applying means to bring the brake disc or disc onto frictional contact with non rotatable structure to brake the shaft. The housing has an inlet (27) into the chamber through which cooling oil may enter the chamber and a closure member (28) for closing off the inlet. The closure member is moveable between open and closed positions by an actuator (40). The chamber has an outlet for allowing cooling oil to leave the chamber and a control means (50) is provided for activating the actuator (40) to move the closure member (28) to close the inlet when the associated vehicle achieves one or more vehicle predetermined operating conditions so that the rotating brake disc or discs or a component rotating therewith can pump oil from the chamber and hence reduce the viscous drag caused by the rotation of the brake disc or discs within the chamber. For example, the control means closes the inlet when the vehicle has been driven at a predetermined vehicle speed for a predetermined time period.</p> |